Air Pollution: The Public Health Challenge of our Time Professor Stephen Holgate, Advisor to Royal College of Physicians.
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e are constantly being told by Government Ministers that air quality in the UK is improving. While the closure of coal-fired power stations has improved air quality nationally in urban areas, where traffic is the major pollution source, better air quality has proven much more difficult to achieve. At the same time evidence as to the harmful effects of air pollution has been rapidly increasing, particularly in relation to small particulates with a diameter of less than 2.5 microns, known as PM2.5. We also believe that ultrafine particles (PM0.1 or nanoparticles), are even more dangerous due to their enhanced ability to bypass the lung barrier, thereby accessing the blood stream and penetrating tissues, including the brain and the placenta. 1,2,3. These particles are coated with metals, cancer-causing compounds such as benzo-a-pyrene, and other organic substances. Once deposited in tissues they induce “oxidative stress” and inflammation, causing cells to die more quickly. Virtually every organ is susceptible to their damaging effects and it is for this reason that air pollution is the public health challenge of our time. Negligence on this issue appears particularly callous given the most vulnerable members of 4
Figure 1. Overview of diseases, conditions, and biomarkers affected by outdoor air pollution. Conditions currently included in the Global Burden of Disease categories are shown in bold
our society often suffer the effects of air pollution disproportionately. It is generally agreed that NO2 aggravates asthma, and peak levels relate to increased hospital admissions .4,5.
“Virtually every organ is susceptible to the damaging effects of Air Pollution” In February 2013, Ella Kissi -Debrah, a nine year-old girl living close to the South Circular Road in London, suffered a fatal asthma attack after being admitted to hospital 27 times over a 3 year period.
I discovered a “striking association” between her admissions to hospital and pollution levels near her home, including NO2. In London and other major cities, up to eighty per cent of NO2 is derived from diesel vehicles. 38 out of 43 areas in the UK have been in breach of EU air quality standards for NO2 since 2010. New vehicles with tighter emission standards have not produced the expected improvements in air quality due to gaming of the emissions tests by car manufacturers, and cheating in the case of the Volkswagen who fitted NO2 reduction technology that only operated under laboratory conditions. Under real driving conditions, these “cheat” devices turned off NO2 controls resulting in emissions from diesel vehicles that were 30 to 40 times
